The development mode is an important part of the deepwater oil & gas developments including surface floating platform, subsea production system and gas/oil transportation. Various reasons such as, geological location, reservoir size, well pattern, experience of operators etc., may have a great influence on the development mode. How to select the optimum development mode is a decisive factor in the development costs, risks and flexibility in later stages for deepwater oil & gas fields. Based on reservoir data, site characteristics of the fields, applicable local rules and oil company marketing strategy, the screening process can be employed to eliminate all of the impracticable options and find the optimum development option in terms of technical and economic feasibility. In order to make the selection process more objective and effective, we attempt to develop a model for the development option of deepwater oil and gas fields to analyze the validity of existing development modes in this paper. The results can provide the engineers some references in the front end engineering studies.

INTRODUCTION

With the offshore oil & gas development developing from shallow water to ultra-deep water, some oil-rich sea area has become the focus in the field of global gas & oil developments, such as Gulf of Mexico(GOM), Brazil, West Africa and so on(Zhang and Chen,2009;Tian and Yang,2006). And, the development mode of representative deepwater oil & gas in these sea areas has naturally become the research focus in recent years. According to the subsea well type, the development mode can be generally classified into three basic types: dry tree, wet tree, and the mix of the two (Often et al.,2001;Wang et al.,2010). In the dry tree development mode, Christmas trees are installed above water, usually on platforms like TLP, Spar, etc. Advantages of this mode include its convenience of drilling, maintenance and its high production efficiency.